Ascariasis

History

Fact

Explanation

Cough, dyspnoea, wheeze and chest pain.

When migrating through the lungs, Ascaris larvae secrete allergenic substances which stimulate the activation of the IgE mediated immune response which in turn lead to pathophysiological changes in the lung such as airway inflammation and bronchial hyper reactivity [1].

Due to small bowel obstruction, commonly as a result of large numbers of entangled worms. A worm bolus could also result in volvulus and intussusception which could cause bowel ischemia and infarction [2].

GANNONA P.F.G., D.T. NEWTONB, C.F.A. PANTINB and P.S. BURGEA. Effect of the number of peak expiratory flow readings per day on the estimation of diurnal variation. Thorax[online] 1998, 53:790-792 [viewed 14 April 2014] Available from: DOI: 10.1136/thx.53.9.790

Investigations - for Diagnosis

Fact

Explanation

Stool examination for fertilized ova.

Fertilized ova of the adult worm are unequally excreted over days and patchily distributed in stool, so stool smears should be examined over several days [1].

Full blood count revealing eosinophilia.

Secondary eosinophilia due to tissue invasive parasitosis [2].

Ascaris larvae in sputum.

Due to migration of larvae through the lungs in the pulmonary phase [3].

Transient pulmonary infiltrates on chest X ray.

Occurs during pulmonary migration of Ascaris larvae [4].

Multiple air fluid levels on erect abdominal X ray.

Due to intestinal obstruction caused by the worms [5].

Ultrasound scanning of the biliary tree.

It has the ability to demonstrate the presence of biliary ascariasis with findings such as bile duct dilatation and by directly visualizing worms within the biliary tree [6].